(a) Field of the Invention
The present invention is related to an energy storage type of dual-drive coupled power distribution system, and more particularly to one that provides real time power distribution for the kinetics to drive the front wheel and the rear wheel by an all wheel driving carrier for promoting drivability and drive safety under severe road and weather conditions and for operating with hybrid function.
(b) Description of the Prior Art
Conventional all wheel driving (AWD) is generally referred to four wheel driving, respectively two front wheels and two rear wheels; two front and one rear, or one front wheel and two rear wheels driving; or six-, even up to eight-wheel driving with additional rear wheels. Currently AWD is roughly classified into two systems:
(1) Full Time Driving: the engine power drives both of the front and the rear wheels in full time, and an additional differential damper such as the VW's SYNCRO is each disposed between the power source and the motive power side, as well as the power source and the rear wheel set. The advantages of this pattern include that both of the front and the rear wheels are given driving power and good driving performance while flaws including greater power loss and higher fuel consumption are observed.
(2) Real Time Driving: in this pattern, a controllable clutch subject to mechanical, electromagnetic, or fluid force is disposed between the rear wheels and the power source; when driving warrants, the clutch is closed up through the control by manual or automatic detection to drive the rear wheels, otherwise the front-drive takes over in case of general road conditions to save fuel consumption. However, this pattern, either in manual or automatic control mode, an immediate response is prevented when the road condition warrants since there is a slight delay in the timing for the rear wheels to generate kinetics.
(3) Alternatively, an intermediate differential wheel set is provided between the front and the rear wheels; however, the flaw of this pattern is that either differential output end skids, the other differential output end loses its power. That is, if the front wheel skids, the rear wheel is deprived of its power.
All those three patterns described above share the common flaw that once either wheel set skids, the other wheel set loses its power. If an additional anti-skid damper is mounted, it means more lose of power, accelerated temperature rise to the mechanical parts, and significant drop of power performance to result in:
1. In case of bumpy road condition, the rear wheels are prevented from engaging in asynchronous drive with the front wheels, for example, under circumstances when the rear wheels must run faster than the front wheel do.
2. In case of climbing a slope, or upon starting up under heavy load, controlling the rear wheels to produce power greater than that by the front wheels fails.
3. Distribution of power for the front and the rear wheels at random is impossible.